Wireless Doorbell with DVR
It sounds pretty ingenious -- a wireless doorbell with a hidden camera that records everyone who comes to your door. Most of these systems record high-resolution images (with audio) in a memory card that you can insert into your computer or phone, allowing you to see who's been at your home. The only catch is -- the system is activated only when the doorbell is pressed. So sure, it could come in handy if you realize you just missed the doorbell ringing and want to know who was there (or if you're just curious about who rings your doorbell while you're away), but it probably won't help you catch a thief -- unless that thief happened to ring the doorbell before he broke in to your home.